A National Perspective of Patellar Instability in Children and Adolescents in the United States: MPFL Reconstruction Is Three Times Higher Than the Incidence of Isolated Lateral Release


      The objective was to (1) evaluate any recent changes in the United States in the incidences of medial patellofemoral ligament (MPFL) reconstruction and isolated lateral release for patellar instability in children and adolescents, (2) identify concomitant procedures with MPFL, and (3) report national complication rates after MPFL reconstruction with and without concomitant procedures in children and adolescents.


      A national database was queried for patients aged 5 to 18 years who underwent operative treatment for patellar instability from 2010 to 2018. Inclusion criteria were either an MPFL reconstruction or lateral release for a diagnosis of patellar instability. Concomitant procedures with MPFL reconstruction assessed were tibial tubercle osteotomy, associated arthroscopic procedures, and lateral release. Changes in incidence in MPFL reconstruction, lateral release and concomitant procedures were assessed. The following postoperative complications were assessed: knee stiffness, infection, patella fracture, and growth arrest or angular deformity.


      2,161 patients who underwent MPFL reconstruction and 1,159 patients who underwent isolated lateral release for patellar instability were identified. The incidence of MPFL reconstruction in adolescents from 2010 to 2018 did not change significantly (2010: 7.11, 2018: 5.91, P = .137), while isolated lateral release decreased (2010: 6.06, 2018: 1.83, P < .0001). Concomitant procedures with MPFL reconstruction were common, with arthroscopy being the most frequent (58-67%). The most common complication within 90 days of surgery was patella fracture (0.4% to 2.0%). Infection (0.4% to 1.0%) and growth arrest (0.09% to 0.61%) were the least common. MPFL and arthroscopy had a decreased risk of growth arrest following surgery compared to MPFL alone (P = .038).


      The incidence of MPFL reconstruction remained high from 2010 to 2018, while isolated lateral release decreased during the same time period. Complications after MPFL reconstruction, isolated lateral release, and concomitant procedures were infrequent, with postoperative patella fracture the most common.

      Level of Evidence

      IV, case series
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        • Platt B.N.
        • Bowers L.C.
        • Magnuson J.A.
        • et al.
        Return to sport after medial patellofemoral ligament reconstruction: A systematic review and meta-analysis.
        Am J Sports Med. 2021; (363546521990004)
        • Xu J.-C.
        • Zhang B.-X.
        • Jia Y.-F.
        • et al.
        Medial patellofemoral ligament reconstruction using suture tape for patellofemoral joint instability.
        Orthop Surg. 2021; 13: 847-854
        • Baron J.E.
        • Khazi Z.M.
        • Duchman K.R.
        • Westermann R.W.
        Risk factors for opioid use after patellofemoral stabilization surgery: A population-based study of 1,316 cases.
        Iowa Orthop J. 2020; 40: 37-45
        • Baer M.R.
        • Macalena J.A.
        Medial patellofemoral ligament reconstruction: patient selection and perspectives.
        Orthop Res Rev. 2017; 9: 83-91
        • Nietosvaara Y.
        • Aalto K.
        • Kallio P.E.
        Acute patellar dislocation in children: Incidence and associated osteochondral fractures.
        J Pediatr Orthop. 1994; 14: 513-515
        • Palmu S.
        • Kallio P.E.
        • Donell S.T.
        • Helenius I.
        • Nietosvaara Y.
        Acute patellar dislocation in children and adolescents: A randomized clinical trial.
        J Bone Joint Surg Am. 2008; 90: 463-470
        • Redler L.H.
        • Wright M.L.
        Surgical management of patellofemoral instability in the skeletally immature patient.
        J Am Acad Orthop Surg. 2018; 26: e405-e415
        • Schneider D.K.
        • Grawe B.
        • Magnussen R.A.
        • et al.
        Outcomes after isolated medial patellofemoral ligament reconstruction for the treatment of recurrent lateral patellar dislocations: a systematic review and meta-analysis.
        Am J Sports Med. 2016; 44: 2993-3005
        • Schorn D.
        • Yang-Strathoff S.
        • Gosheger G.
        • et al.
        Long-term outcomes after combined arthroscopic medial reefing and lateral release in patients with recurrent patellar instability—a retrospective analysis.
        BMC Musculoskelet Disord. 2017; 18: 277
        • Krebs C.
        • Tranovich M.
        • Andrews K.
        • Ebraheim N.
        The medial patellofemoral ligament: Review of the literature.
        J Orthop. 2018; 15: 596-599
        • Maffulli N.
        • Aicale R.
        • D’Addona A.
        • Young D.A.
        • Kader D.F.
        • Oliva F.
        Combined medial patellofemoral and patellotibial reconstruction with soft tissue fixation in recurrent patellar dislocation.
        Injury. 2020; 51: 1867-1873
        • Stupay K.L.
        • Swart E.
        • Shubin Stein B.E.
        Widespread implementation of medial patellofemoral ligament reconstruction for recurrent patellar instability maintains functional outcomes at midterm to long-term follow-up while decreasing complication rates: A systematic review.
        Arthroscopy. 2015; 31: 1372-1380
        • Ellera Gomes J.L.
        Medial patellofemoral ligament reconstruction for recurrent dislocation of the patella: a preliminary report.
        Arthroscopy. 1992; 8: 335-340
        • Trojan J.D.
        • Treloar J.A.
        • Smith C.M.
        • Kraeutler M.J.
        • Mulcahey M.K.
        Epidemiological patterns of patellofemoral injuries in collegiate athletes in the United States from 2009 to 2014.
        Orthop J Sports Med. 2019; 7 (2325967119840712)
        • Arshi A.
        • Cohen J.R.
        • Wang J.C.
        • Hame S.L.
        • McAllister D.R.
        • Jones K.J.
        Operative management of patellar instability in the United States: An evaluation of national practice patterns, surgical trends, and complications.
        Orthopaed J Sports Med. 2016; 4 (2325967116662873)
        • Merchant A.C.
        • Mercer R.L.
        Lateral release of the patella. A preliminary report.
        Clin Orthop Relat Res. 1974; 105: 40-45
        • Danino B.
        • Deliberato D.
        • Abousamra O.
        • Singh S.
        • Klingele K.
        Four-in-one extensor realignment for the treatment of obligatory or fixed, lateral patellar instability in skeletally immature knee.
        J Pediatr Orthop. 2020; 40: 503-508
        • da Fonseca L.P.R.M.
        • Kawatake E.H.
        • Pochini A. de C.
        Lateral patellar retinacular release: Changes over the last ten years.
        Rev Bras Ortop. 2017; 52: 442-449
        • Panni A.S.
        • Tartarone M.
        • Patricola A.
        • Paxton E.W.
        • Fithian D.C.
        Long-term results of lateral retinacular release.
        Arthroscopy. 2005; 21: 526-531
        • Lattermann C.
        • Drake G.N.
        • Spellman J.
        • Bach B.R.
        Lateral retinacular release for anterior knee pain: A systematic review of the literature.
        J Knee Surg. 2006; 19: 278-284
        • Ricchetti E.T.
        • Mehta S.
        • Sennett B.J.
        • Huffman G.R.
        Comparison of lateral release versus lateral release with medial soft-tissue realignment for the treatment of recurrent patellar instability: a systematic review.
        Arthroscopy. 2007; 23: 463-468
        • Pagenstert G.
        • Wolf N.
        • Bachmann M.
        • et al.
        Open lateral patellar retinacular lengthening versus open retinacular release in lateral patellar hypercompression syndrome: a prospective double-blinded comparative study on complications and outcome.
        Arthroscopy. 2012; 28: 788-797
        • Hughston J.C.
        • Flandry F.
        • Brinker M.R.
        • Terry G.C.
        • Mills J.C.
        Surgical correction of medial subluxation of the patella.
        Am J Sports Med. 1996; 24: 486-491
        • Bedi H.
        • Marzo J.
        The biomechanics of medial patellofemoral ligament repair followed by lateral retinacular release.
        Am J Sports Med. 2010; 38: 1462-1467
        • Shah J.N.
        • Howard J.S.
        • Flanigan D.C.
        • Brophy R.H.
        • Carey J.L.
        • Lattermann C.
        A systematic review of complications and failures associated with medial patellofemoral ligament reconstruction for recurrent patellar dislocation.
        Am J Sports Med. 2012; 40: 1916-1923
        • Parikh S.N.
        • Nathan S.T.
        • Wall E.J.
        • Eismann E.A.
        Complications of medial patellofemoral ligament reconstruction in young patients.
        Am J Sports Med. 2013; 41: 1030-1038
        • Shultz C.L.
        • Schrader S.N.
        • Packard B.D.
        • Wascher D.C.
        • Treme G.P.
        • Richter D.L.
        Is diagnostic arthroscopy at the time of medial patellofemoral ligament reconstruction necessary?.
        Orthopaed J Sports Med. 2020; 8 (2325967120945654)
        • Gao G.
        • Liu P.
        • Xu Y.
        Treatment of patellar dislocation with arthroscopic medial patellofemoral ligament reconstruction using gracilis tendon autograft and modified double-patellar tunnel technique: minimum 5-year patient-reported outcomes.
        J Orthop Surg Res. 2020; 15: 25
        • Sherman S.L.
        • Welsh J.W.
        • Rund J.M.
        • Oladeji L.O.
        • Worley J.R.
        • Ray T.
        Medial patellofemoral ligament reconstruction with and without tibial tubercle osteotomy.
        Orthop J Sports Med. 2019; 7
        • Sherman O.H.
        • Fox J.M.
        • Sperling H.
        • et al.
        Patellar instability: treatment by arthroscopic electrosurgical lateral release.
        Arthroscopy. 1987; 3: 152-160
        • Fink C.
        • Veselko M.
        • Herbort M.
        • Hoser C.
        MPFL reconstruction using a quadriceps tendon graft: part 2: operative technique and short term clinical results.
        Knee. 2014; 21: 1175-1179